Alexia
by mermaid12108
Summary: Five years ago, Isabelle ran away from the Institute for no reason. Then, something draws her back to new york, and the shadowhunters soon discover why she left. The answer is pretty clear when she comes back with a daughter that is half shadowhunter, half vampire-Her and Simon's daughter.
1. Chapter 1: They found her

**Chapter Songs: **

**Crimes~Damien Rice **

**Almost Lover~A Fine Frenzy **

**Holding Out For A Hero~Ella Mae Bowen **

^Isabelle^

Mommy, wake up!" Whined the little girl in protest, jumping up and down on her mothers bed. "Alexia, stop it!" Isabelle grumbled, burying herself deeper into the pillows. "But momma, someones here! They wanna see you!" Isabelle shot upright in bed, heart pounding. _They'd found her. _"Where?"

"Out here! He has weird tattoos on. I want one! Can I have one?"

"No." She grabbed her daughter and slowly walked out of her bedroom in the apartment, her heart in her throat. There was a form on the couch, and for a moment, a blaze of ice cold fear shot through her, but then she recognized it as her brother. "Alec." Isabelle whispered, eyes wide. He stood up, lightning fast, and she barely had time to put Alexia down before she was wrapped in a tight embrace. "Where the hell have you been?" Alec asked into her shoulder, but she didn't respond. Couldn't, with the tears clogging her throat. And then something extremely rare happened. Isabelle Lightwood cried.

_`-_Simon_-` _

Simonhad never been so anxious his entire life, both human and downworlder. The words kept echoing in his head. _They've found her. She's on her way here. _"Stop it!" Clary commanded, putting her hand on his knee to make it stop bouncing. "Sorry." He said, crossing the leg over his other. "I'm just…nervous."

"Really? I never could've guessed. Si, just…stop freaking. It'll be fine."

The diamond ring on her left finger glittered as she gestured to his now drumming fingers. A few weeks ago, she and Jace had announced that they were engaged. He was happy for them, no mistake, but Simon couldn't help thinking what might've been. What olive-skinned finger could've been wearing a ring like that. A door slammed, and Clary and him both stood up at the same time. "Let me go." She said softly. It took everything in him not to throw caution into the wind and race into the corridor right that very moment. But all he did was nod, digging his fingers of the soft velvet lining the armchair as she left. "Hey I—Oh, hi there. I don't believe I've meet you before." Clary's voice said.

And then a tiny, little kid voice, "Hi! Mommy says you're my aunt Clary! I'm Alexia."

That was it. He couldn't take it anymore. He bolted into the corridor. Then he just sort of…froze. Isabelle looked up, and also froze. Her lips were parted, words on the edge of them. He took a step forward, but then his legs were tackled. A little girl was hugging his legs and giggling, all while grinning up at him and bouncing. "Hi! Hi! Hi!" She looked just like Isabelle. With her long black hair, and…and…and eyes that looked back at him in the mirror everyday. She had Isabelle's mouth, but a nose just like his. "Hello." He smiled down at the child softly, ruffling up her hair. "Okay, Lexi, let's go put up our stuff."

"Okay! I'll see you later, Mommy's friend." She showered in his ear when her bent down at his level. He nodded, and then caught Isabelle''s gaze. His look promised questions later.


	2. Chapter 2: Old Flames Keep Burning

**Chapter Song(s): **

**Love the way you lie~Ariana Grande**

**Stay~Leroy Sanchez **

**Never Let Me Go~Florence+The Machines**

**Black Flies~The Frontier City **

_`-_Simon_-` _

"Who is she?" Simon asked as soon as the door closed behind of Isabelle. He only barely caught a glimpse of the little girl sleeping in the big bed. She looked so_ tiny_.

"She's my daughter."

"But who's her father?" He said, his voice coming out more broken than he realized it could.

She looked down, and then grabbed his wrist and dragged him behind her. He could've resisted her, no problem. It just felt so good to have his skin against hers again. The door clicked close behind them, and then he realized whose room it was. Hers. "Wow, it's like I never left."

"Who's room is my daughter staying in?"

"Alec's. And how did you figure it out?"

"It's not really that hard. She looks like both me and you."

"Yeah. I have a lot of explaining to do."

"No shit."

"But first…"

"What, are you gonna take a selfie?"

She gave a short laugh. "No. But first, I just want to kiss you again." She closed the small distance between them and brought her lips down on his. It was just a brush, but he wasn't having any of this hesitant nonsense. He gripped her face in his hands and kissed her with a hunger that always settled down to a deep ache in him every day. One had fisted in her silky hair, the other touching the smooth skin at her waist, brushing the edge of her sweater. She looked so different than he remembered, yet all the same. He'd memorized every edge of her, every tiny detail, right down to the tiny freckle on the back of her hand. Her hair was shorter, going just past her shoulders and inch or two. She was also wearing jeans, and a thin tank top with a sweater over it. Grey, and V-neck, which just made her eyes stand out more. He tugged that sweater off now, as well sat the tank top. Sure, she was beautiful in them, but they needed to go. It had been so long since her skin had been against his. The air seemed to be tinged with electricity, and he had never felt more alive. His shirt went, too, tossed somewhere he couldn't bring himself to care one bit about. He kissed every perfect inch of her, hooking her legs around his waist. Her arms wound around his neck, touching the edges of his hair. Simon breathed in her taste, her smell, took in every part of her that meant the world to him. Everything.

_^Isabelle^ _

As her back hit the bed, she broke away to trace the hard lines of his stomach, the curve of his jawline which was now just dotted here and there with stubble. It seemed impossible, but it was almost as if he had…aged, just like she had. She was now twenty two, which had to make him at least twenty three. "You have no idea how much you mean to me." The word came out in just a whisper, but it made her impossibly happy to hear them. It felt like this was their private universe, nothing else mattering. "Then show me." She whispered.

He did.

**oOo**


	3. Chapter 3: Well This Is Awkward

"Isabelle?" Simon continued to run his hands through her hair, but she froze.

"Yes?" She asked.

"When were you going to tell you I had a daughter?"

"At some point."

"So...never."

"Not exactly."

"But why did you leave?"

"I had to hide her, before telling anyone I was even pregnant."

"It would've been nice to let me know."

"But then you wouldn't have let me leave. I had to hide her, because of what we are—and in turn what she is. I'm a Shadowhunter, you're a vampire, and she's part both, if I'm correct. You know how the Clave was—is. They're paranoid. You see what they did to Helen. I couldn't let anything happen to any of us."

Simon sighed. "I know, but a text would've been nice."

"Believe me, I wanted to, but that wasn't an option."

Simon nodded. They lay there for a minute, and then there was a small knock at the door. "Mommy?"

They both sat up.

"Hide!" Isabelle said.

"Why? She's a five year old!"

"A five year old that doesn't need to know how she was made!" Simon rolled his eyes but had his jeans on in record time and threw his shirt to Isabelle. He hid in the bathroom just as the door opened, revealing Alexia holding her teddy bear by its arm. "Mommy? Aunt Clary says it's time for dinner."

"Okay. Just let mommy get dressed."

"What were you doing?"

"Taxes."

"What are taxes?"

"Grown up things."

"Okay..."

Clary, thankfully, showed up then. "Come on, Alexia. Let's let mommy to finish her...taxes." At that the redhead winked at Isabelle but took the five years old away, shitting the door behind them. Isabelle sighed and dropped her face into the pillow.

"Is the new word for sex 'taxes'?"

"Shut up."

She heard his laughter before she lifted her head. "You should probably get out before anyone gets any ideas."

"So I'm just a booty call then? I knew it."

"You're different." She observed.

"Good different or bad different?"

"Good different."

"I guess that's good. So, I hate to sound cliché, but where does this leave us?"

"I don't know." Isabelle admitted.

"Let's just decide after the awkward dinner that awaits."

She nodded. "Yeah." She agreed softly, watching him leave. She had to make herself remember that it wasn't permanent, not like last time. She threw her clothes back on and was running a brush through her unruly hair when there was a knock at the door. When she opened it she saw Jace standing there, still in his gear. He looked out of breath and disheveled, as if he had run for miles. He looked at her with wide eyes, shaking his head. "I'd heard, but..." She threw her arms around him, squeezing tightly. Not a moment later, she felt him do the same. "We thought you were dead, Iz." He said into her hair. "We all did, except blo—Simon. You really know how to hide yourself."

Isabelle pulled away, nodding. "Yeah, well, I had reason."

"Yeah, I heard. Apparently Alec and I have a niece."

"Yep."

"Wow. This is one of the weirdest and most awkward conversations I've had lately."

After that, Isabelle finished with her hair and headed down. Now everyone but her had to be down there. When she walked into the institute's huge dining room, her worries were confirmed.


	4. Chapter 4: The Road Ahead

"Okay." Isabelle sat on the bed next to her daughter, smoothing her hair down. "What story do you want to hear tonight?"

"I dunno."

Isabelle laughed, smiling down at Alexia. "Well how are we going to have story time without a story?"

"Make one up!" Alexia said, playing with the bracelet around her wrist. The silver glittered in the light as she twisted it.

Isabelle nodded. "Okay." She said, and began the telling of a story that was anything but make believe.

"Once upon a time, there was a boy and girl. The girl was a strong warrior, with a duty to protect mun—or, um, people. And the boy was a creature of the night—but he wasn't like the others. He was special. Unlike the other evil, nasty creatures, he could walk in the sun. He wasn't evil at all. He was one of the good guys. The boy and girl fell madly in love. And they had a baby girl. Their daughter was the prettiest baby that had ever existed. Almost everybody loved her." Alexia's eyes had began to droop.

"But some evil people wanted to hurt the baby."

"Wha happened?" Alexia said, barely even whispering. Her eyes were completely shut by this point. It wasn't until she heard the soft snores did Isabelle finished the story.

"The girl took her baby and ran far, far away to where no one would ever hurt them. Five years later, they came back. What happened to them? Well, we'll just have to wait and see, won't we?" Isabelle leaned down and kissed her daughters forehead, wishing she knew what was in store.

Isabelle padded to her room, pausing to take a deep breath and then pushing the door open. The person who sat up from the couch was not at all who she thought it would be. "Clary?" Isabelle said, shock filtering through her system. She had thought she would find Simon, most likely sprawled across her bed in a position that could only be comfortable to him. Alexia did that so often it was crazy. She had planned to tell him everything, but that would obviously have to wait. Clary smiled at her, giving her a tiny wave."Hey."

"What are you doing here?" Isabelle still couldn't get the shocked look off her face.

"Well, I wanted to talk to you. You know, catch up. Dinner obviously wasn't a good time to do that."

Oh, yeah. Isabelle knew that. As soon as she had sat down, Mayrse had started lecturing her. It seemed Isabelle would never be able to escape those, even though she was now a mother herself. "Yeah, it really wasn't."

"Well, um, first off." Clary's walked up and wrapped her arms around Isabelle. The girl may be tiny, but she could hug like no one else. Isabelle hugged her back, admitting that she had missed her.

She had missed everyone.


End file.
